Mac Pro Ram Q

opak

macrumors newbie
Original poster
Nov 6, 2005
10
0
Montreal, Canada
My question is if I my mac pro comes with 1Gb ram (2x512mb) and I want to upgrade with 4G (2x2Gb), will I be able to keep the original stick on it so it becomes 5Gb ram? I hear somewhere that the ram stick needs to match or something. :confused:

Anybody knows anything about this?

Thanks!
 

dpaanlka

macrumors 601
Nov 16, 2004
4,868
6
Illinois
My question is if I my mac pro comes with 1Gb ram (2x512mb) and I want to upgrade with 4G (2x2Gb), will I be able to keep the original stick on it so it becomes 5Gb ram? I hear somewhere that the ram stick needs to match or something. :confused:

Anybody knows anything about this?

Thanks!
Yeah I just upgraded my system with 4GB (4x1GB) and the 512s still worked fine.

However I decided to take my 512s out so that I could make room for an additional four 1GB modules and have fun quad channel memory access (thats what the matching is about).
 

opak

macrumors newbie
Original poster
Nov 6, 2005
10
0
Montreal, Canada
Yeah I just upgraded my system with 4GB (4x1GB) and the 512s still worked fine.

However I decided to take my 512s out so that I could make room for an additional four 1GB modules and have fun quad channel memory access (thats what the matching is about).
Thanks for the info! Additional question if you may.
Is there any reason why you chose 1Gb sticks instead of 2Gb sticks? (Since they cost the same for 4Gb kits.)

Thanks! :)
 

dpaanlka

macrumors 601
Nov 16, 2004
4,868
6
Illinois
Thanks for the info! Additional question if you may.
Is there any reason why you chose 1Gb sticks instead of 2Gb sticks? (Since they cost the same for 4Gb kits.)
If you install in equal sets of four allows you to benefit from quad channel memory access.
 

ironic23

macrumors 6502
Feb 8, 2006
263
0
If you install in equal sets of four allows you to benefit from quad channel memory access.
do they have to be equal sets of four (i.e. 4x1gb sticks) or just sets of four (i.e. 2x1gb + 2x2gb sticks)? i think it is the latter, but correct me if i am wrong.
 

SDAVE

macrumors 68040
Jun 16, 2007
3,381
436
Nowhere
If I were you I'd get 2GB sticks. I have 2GBx4 (OWC) right now with 512x2 (Apple RAM) for a total of 9GB. Works like a charm. Don't waste your money on 4GB sticks, they're too expensive and don't get 1GB sticks, it won't leave you room for upgrades later on.
 

dpaanlka

macrumors 601
Nov 16, 2004
4,868
6
Illinois
do they have to be equal sets of four (i.e. 4x1gb sticks) or just sets of four (i.e. 2x1gb + 2x2gb sticks)? i think it is the latter, but correct me if i am wrong.
Equal sets of four. So 4x1gb. They have to be placed in a certain way, too.

If I were you I'd get 2GB sticks. I have 2GBx4 (OWC) right now with 512x2 (Apple RAM) for a total of 9GB. Works like a charm. Don't waste your money on 4GB sticks, they're too expensive and don't get 1GB sticks, it won't leave you room for upgrades later on.
I have 4x1gb, and I still have four open slots. OWC makes 4gb modules now, I can't perceive me needing more than the 20gb of memory I can still upgrade this thing to by the time I replace it.
 

RJS9S

macrumors member
Jun 28, 2007
37
0
so to get the quad processor to actually kick in you need to have both slates full with equil amounts of ram sticks?
 

suneohair

macrumors 68020
Aug 27, 2006
2,137
0
Equal sets of four. So 4x1gb. They have to be placed in a certain way, too.



I have 4x1gb, and I still have four open slots. OWC makes 4gb modules now, I can't perceive me needing more than the 20gb of memory I can still upgrade this thing to by the time I replace it.
2GB Dimms are cheaper by the GB at this point. It makes sense to go with 2GB DIMMs. IMO.
 

ironic23

macrumors 6502
Feb 8, 2006
263
0
Equal sets of four. So 4x1gb. They have to be placed in a certain way, too.
Where did you get that? As far as i've read from a review on Anandtech and some other documentation (can't remember what), you just have to fill it with 4 sticks of RAM (2 pairs) regardless of size to get the quad channel working.
 

dpaanlka

macrumors 601
Nov 16, 2004
4,868
6
Illinois
Where did you get that? As far as i've read from a review on Anandtech and some other documentation (can't remember what), you just have to fill it with 4 sticks of RAM (2 pairs) regardless of size to get the quad channel working.
I don't think so.

so to get the quad processor to actually kick in you need to have both slates full with equil amounts of ram sticks?
Not quad processor, quad channel memory access. Basically faster memory for memory-intensive applications.
 

anim8or

macrumors 65816
Aug 16, 2006
1,362
9
Scotland, UK
confused....

sorry, but i am confused.

Im about to get a Mac Pro and was gonna stay with the standard 2x512mb ram and then add either another 2x512mb or 2x1gb configuration...

Correct me if im wrong.........

The top RAM tray is riser A and the bottom is B?

So i have to have slot 1 in A and B matching eg 512mb in each....

So i can then put 1gb ram in slot 2 of A and B???
 

hayduke

macrumors 65816
Mar 8, 2005
1,177
2
is a state of mind.
sorry, but i am confused.

Im about to get a Mac Pro and was gonna stay with the standard 2x512mb ram and then add either another 2x512mb or 2x1gb configuration...

Correct me if im wrong.........

The top RAM tray is riser A and the bottom is B?

So i have to have slot 1 in A and B matching eg 512mb in each....

So i can then put 1gb ram in slot 2 of A and B???
A is top B is bottom and each has four slots. You want to install by pairs in A and B. That is, but two in the slots 1/2 of A then put two in slots 1/2 of B, then in 3/4 of A, then 3/4 of B. So, 2x512MB in 1/2 of A is how it will come installed. If you buy 2x512 then they can go in 1/2 of B. If you buy 2x1GB, however, you should but those in 1/2 of A and but the 2x512MB in 1/2 of B. You can do this by simply swapping the A/B card since the 2x512MB is already installed. Capice? HTH.
 

anim8or

macrumors 65816
Aug 16, 2006
1,362
9
Scotland, UK
thank you that seems to have cleared it up for me,

I didnt realise you could just swap tray A and B, that is very cool.

Agian thanks for the quick response
 

MacTO

macrumors member
Apr 3, 2007
89
0
A is top B is bottom and each has four slots. You want to install by pairs in A and B. That is, but two in the slots 1/2 of A then put two in slots 1/2 of B, then in 3/4 of A, then 3/4 of B. So, 2x512MB in 1/2 of A is how it will come installed. If you buy 2x512 then they can go in 1/2 of B. If you buy 2x1GB, however, you should but those in 1/2 of A and but the 2x512MB in 1/2 of B. You can do this by simply swapping the A/B card since the 2x512MB is already installed. Capice? HTH.
What he said is right.

But if you ever forget it again, take a look at 3 GB in this configuration chart. In case, why don't you just print it off and keep it handy so that you don't get confused when your Mac Pro arrives. :apple:

http://homepage.mac.com/tribe3/.Pictures/MemConfig.jpg